emissivity.org

License

CC-BY 4.0 International.

All spectral data in EKHI is released under the Creative Commons Attribution 4.0 International (CC-BY 4.0) license. You are free to:

Share — copy and redistribute the data in any medium or format.
Adapt — remix, transform, and build upon the data for any purpose, including commercial.

The only requirement is attribution. You must cite both the original publication (the source paper) and the EKHI database record from which you obtained the data.

Full license text: creativecommons.org/licenses/by/4.0/

Citation format

Citing the EKHI database itself.

When referring to EKHI as a whole (e.g., in a methods or data-availability section), cite the data descriptor in Scientific Data. The frozen dataset behind it is also archived on figshare under its own DOI; cite that when you used the archived snapshot rather than the live database.

Plain text — data descriptor

        Gabirondo-López, J. et al. EKHI: an open database of optical and

        thermal radiative properties of solids. Scientific Data 13, 740 (2026).

        https://doi.org/10.1038/s41597-026-07083-9

Plain text — archived dataset

        Gabirondo-López, J. et al. EKHI: an open database of optical and thermal radiative properties of solids — initial dataset. figshare (2026).

        https://doi.org/10.6084/m9.figshare.30581240 (CC BY 4.0)

BibTeX

        @article{ekhi2026,

          author  = {Gabirondo-L{\'o}pez, J. and others},

          title   = {{EKHI}: an open database of optical and thermal radiative properties of solids},

          journal = {Scientific Data},

          volume  = {13},

          pages   = {740},

          year    = {2026},

          doi     = {10.1038/s41597-026-07083-9}

        }

        @misc{ekhi2026data,

          author    = {Gabirondo-L{\'o}pez, J. and others},

          title     = {{EKHI} dataset},

          publisher = {figshare},

          year      = {2026},

          doi       = {10.6084/m9.figshare.30581240}

        }

Dataset citation

Citing an individual record.

When using specific spectral data from EKHI, cite both the original publication and the EKHI record. Each EKHI record is identified by the DOI of its source publication followed by the curve number within that publication, written <source DOI>:<curve n>, and lives under the publication's page at thermomat.ehu.eus/ekhi.

Step 1 — cite the source publication

        [Authors]. [Title]. [Journal], [Volume], [Pages], [Year].

        DOI: [doi]

Step 2 — cite the EKHI record

        EKHI record [source DOI]:[curve n],

        https://thermomat.ehu.eus/ekhi/publication/[id]/

        (accessed [date])

Example — in a data-availability statement

        "Spectral emissivity data for tungsten were taken from

         de Vos (1954), doi:10.1016/s0031-8914(54)80182-0, as

         EKHI record 10.1016/s0031-8914(54)80182-0:1,

         https://thermomat.ehu.eus/ekhi/publication/22/

         (accessed [date]), reused under CC BY 4.0."

Best practices

Making data reuse transparent.

Always cite the original paper

EKHI is a distribution channel, not the data source. The original authors and their publication deserve primary credit. Dual citation (paper + EKHI) is the expected practice.

Include the EKHI record identifier

Record identifiers of the form <source DOI>:<curve n> (e.g., 10.1016/s0031-8914(54)80182-0:1) make your data provenance unambiguous and allow readers to retrieve the exact curve you used, including measurement conditions and metadata.

State the access date

EKHI is updated at each data release. Including the access date documents which version of the data you used and aids reproducibility if records are corrected or supplemented.

Note any transformations

If you interpolated, smoothed, or converted the data (e.g., directional to hemispherical), state this clearly. Raw EKHI data should be distinguishable from derived quantities.

How to cite and reuse EKHI data.

Need help with data reuse?